Mobile wireless communications device having dual antenna system for cellular and wifi

ABSTRACT

A mobile wireless communications device includes a housing and circuit board carried by the housing. Radio Frequency (RF) circuitry is mounted on the circuit board. A first antenna is supported by the circuit board within the housing and operatively connected to the RF circuitry and configured for cellular phone communications. A second antenna is supported by the circuit board within the housing and operatively connected to the RF circuitry and configured for WiFi communications. The second antenna comprises an inverted-F or monopole antenna having an opening gap that is pointed away from the first antenna.

FIELD OF THE INVENTION

The present invention relates to the field of communications devices,and more particularly, to communications devices that use dual antennasystems.

BACKGROUND OF THE INVENTION

Cellular communication systems continue to grow in popularity and havebecome an integral part of both personal and business communications.Cellular telephones and similar devices allow users to place and receivephone calls most anywhere they travel. Moreover, as cellular telephonetechnology is increased, so too has the functionality of cellulardevices. For example, many cellular devices now incorporate PersonalDigital Assistant (PDA) features such as calendars, address books, tasklists, calculators, memo and writing programs, etc. These multi-functiondevices usually allow users to send and receive electronic mail (email)messages wirelessly and access the internet via a cellular networkand/or a wireless local area network (WLAN), for example, when thedevices include appropriate circuitry for WiFi and other IEEE 802.11WLAN access.

Many of the cellular communications use packet burst transmissions aspart of a Global System for Mobile communications (GSM) system, whichincludes the 850 MHz, 900 MHz, 1800 MHz and 1900 MHz frequency bands.Although these mobile wireless communication devices function as acellular telephone, as noted before, the device can also operate andincorporate Personal Digital Assistant (PDA) features and send andreceive email and other messages wirelessly and across the internet viathe cellular network and/or a wireless Local Area Network (LAN). Thisfunction can include access to “hot spots” as part of a WiFi networkusing IEEE 802.11 standards.

When such devices incorporate WiFi technology, the circuits could beconsidered to describe WLAN products based on IEEE 802.11 standards,using one or more Access Points (APs) as “hot spots” and various numbersof clients. An AP typically broadcasts a Service Set Identifier,“network name” (SSID), using packets called “beacons” by some skilled inthe art, which are broadcast every one hundred or so milliseconds atabout one Mbit\s duration in some non-limiting examples. Some of theseWiFi devices operate in the 2.4 or 5.0 GHz band.

A wireless access point usually connects wireless stations to anadjacent, wired local area network, and is operative similar to anEthernet hub. The access point can relay wireless data to othercompatible wireless devices and to a single, connected local areanetwork device, such as a Ethernet hub or switch. Wireless routers areoften used to integrate a wireless access point with a Ethernet switchand Ethernet router.

In a mobile wireless communications device, if the cellular capabilityis integrated with WiFi capability, often two different antennas areused, for example, a main cellular antenna operative at GSM or otherCDMA band and a WiFi antenna operative in the at least 2.4 GHz band, andsometimes the 5.0 GHz band, making the device not only compatible withcellular GSM communications, but also compatible with WiFicommunications using IEEE 802.11 standards. The antenna designs becomemore challenging, however, as the size and thickness of the mobilephones become smaller to meet marketing requirements and the desires ofend-use consumers. In order to implement multiple antennas in a compactenvironment, the antennas should be designed to reduce the couplingbetween the various antennas. This is necessary not only to enhanceradio performance, but also reduce the cost of implementingElectromagnetic Interference (EMI) filters at harmonic frequencies.Thus, the type of antenna designs used in such devices become importantto reduce the mutual coupling due to the third harmonics between a GSMor similar cellular antenna, operative, for example, at 850 MHz, and aWiFi antenna operative at 2.4 GHz. Isolating these antennas can bedifficult, and different feeding techniques should be introduced toenhance isolation between the two antennas. The two systems, cellular asa Wide Area Network (WAN) and WiFi need to work simultaneously, andthus, isolation between antennas is very critical.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, features and advantages will become apparent from thedetailed description which follows when considered in light of theaccompanying drawings in which:

FIG. 1 is a schematic block diagram of an example of a mobile wirelesscommunications device configured as a handheld device that can be usedin accordance with non-limiting examples and illustrating basic internalcomponents thereof.

FIG. 2 is a front elevation view of the mobile wireless communicationsdevice of FIG. 1.

FIG. 3 is a schematic block diagram showing basic functional circuitcomponents that can be used in the mobile wireless communications deviceof FIGS. 1-2.

FIG. 4 is a plan view showing the interior of a mobile wirelesscommunications device similar to those shown in FIGS. 1 through 3 andshowing in greater detail the relative positioning of a WiFi antenna anda cellular (or GSM) antenna.

FIG. 5 is a fragmentary, side elevation view of the communicationsdevice such as shown in FIG. 4 and showing a fragmentary representationof the circuit board and the configuration of a bottom-fed WiFi antennaformed as an inverted-F antenna, and showing an opening gap facing upand its position relative to the cellular antenna, in accordance with anon-limiting example.

FIG. 6 is a fragmentary, top plan view of the circuit board shown inFIG. 5, and showing the location of the cellular antenna, the locationof WiFi antenna formed as an inverted-F antenna, and location of thegrounding and feeding points at opposite, lower corners of theinverted-F antenna, in accordance with a non-limiting example.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Different embodiments will now be described more fully hereinafter withreference to the accompanying drawings, in which preferred embodimentsare shown. Many different forms can be set forth and describedembodiments should not be construed as limited to the embodiments setforth herein. Rather, these embodiments are provided so that thisdisclosure will be thorough and complete, and will fully convey thescope to those skilled in the art. Like numbers refer to like elementsthroughout.

A mobile wireless communications device includes a housing and circuitboard carried by the housing. Radio Frequency (RE) circuitry is mountedon the circuit board. A first antenna is supported by the circuit boardwithin the housing and operatively connected to the RF circuitry andconfigured for cellular phone communications. A second antenna issupported by the circuit board within the housing and operativelyconnected to the RF circuitry and configured for WiFi communications.The second antenna comprises an inverted-F or monopole antenna having anopening gap that is pointed away from the first antenna.

In yet another aspect, the first antenna is operative at frequencies inthe Global System for Mobile (GSM) communications band (or CDMA). Thesecond antenna is operative at the 2.4 GHz and 5.0 GHz band inaccordance with 802.11 standards. The second antenna can include afeeding point positioned distal from the opening gap at an opposing endfrom the opening gap. The housing can include an upper and lowerportion. In one aspect the first antenna is positioned at a lowerportion of the housing and the second antenna is mounted on the circuitboard at an upper portion of the housing. The opening gap is positionedupward toward the upper portion of the housing in one non-limitingexample.

In yet another aspect, the circuit board can be formed as a ground planefor the first and second antennas. The second antenna is substantiallyrectangular configured in plan view in one non-limiting example andincludes an upper edge that forms the opening gap of the inverted-F ormonopole antenna. A lower edge forms a lower leg of the antenna. Thislower edge or leg could include a feeding point and grounding point atopposite corners thereof, which could be reversed from each other. Inanother non-limiting example, the second antenna can be configured at aquarter or half lamda in length.

In accordance with one non-limiting example, the WiFi antenna isoperative in the 2.4 GHz frequency bands in this non-limiting example,and is bottom-fed relative to the cellular antenna, which is alsopositioned in the housing. This relative positioning reduces mutualcoupling to the cellular, e.g., GSM 850 MHz antenna at its thirdharmonic frequency. For purposes of clarity and description, the termWiFi antenna can refer to any number of antennae that are operative inthese frequency bands in accordance with IEEE 802.11 and similarstandards. Also included under this term WiFi antenna could be differentBluetooth applications.

The WiFi antenna could be a quarter or half lamda long and preferably isformed as an inverted-F or monopole type antenna. The opening gap in theinverted-F or monopole type antenna faces away from the cellular, e.g.,GSM antenna (or CDMA) positioned preferably at the lower portion of thedevice housing. The inverted-F or monopole type WiFi antenna ispositioned on the main Printed Circuit Board (PCB) of the wirelessdevice, such as at an upper portion. This PCB also serves as a groundplane for the antennas. The WiFi antenna includes a feeding point and agrounding point, positioned preferably at the lower portion of theinverted-F or monopole type antenna, opposite the opening gap. These twopositions for the grounding point and feeding point could beinterchangeable. It should also be understood that the inverted-F ormonopole antenna could be used for other non-WiFi applications, such asGPS.

A brief description will now proceed relative to FIGS. 1-3, whichdisclose an example of a mobile wireless communications device, forexample, a handheld portable cellular radio, which can incorporatenon-limiting examples of various circuits that can be used with thecellular antenna and WiFi antenna. FIGS. 1-3 are representativenon-limiting examples of the many different types of functional circuitcomponents and their interconnection, and operative for use with theantenna as later described below.

Referring initially to FIGS. 1 and 2, an example of a mobile wirelesscommunications device 20, such as a handheld portable cellular radio isfirst described. This device 20 illustratively includes a housing 21having an upper portion 46 and a lower portion 47, and a dielectricsubstrate (i.e., circuit board) 67, such as a conventional printedcircuit board (PCB) substrate, for example, carried by the housing. Ahousing cover (not shown in detail) would typically cover the frontportion of the housing. The term circuit board 67 as used hereinaftercan refer to any dielectric substrate, PCB, ceramic substrate or othercircuit carrying structure for carrying signal circuits and electroniccomponents within the mobile wireless communications device 20. Theillustrated housing 21 is a static housing, for example, as opposed to aflip or sliding housing, which is used in many cellular telephones.However, these and other housing configurations may also be used.

Circuitry 48 is carried by the circuit board 67, such as amicroprocessor, memory, one or more wireless transceivers (e.g.,cellular, WLAN, etc.), which includes RF circuitry, including audio andpower circuitry, including any keyboard circuitry. It should beunderstood that keyboard circuitry could be on a separate keyboard,etc., as will be appreciated by those skilled in the art. A battery (notshown) is also preferably carried by the housing 21 for supplying powerto the circuitry 48. The term RF circuitry could encompass theinteroperable RF transceiver circuitry, power circuitry and audiocircuitry.

Furthermore, an audio output transducer 49 (e.g., a speaker) is carriedby an upper portion 46 of the housing 21 and connected to the circuitry48. One or more user input interface devices, such as a keypad(keyboard) 23 (FIG. 2), is also preferably carried by the housing 21 andconnected to the circuitry 48. The term keypad as used herein alsorefers to the term keyboard, indicating the user input devices havinglettered and/or numbered keys commonly known and other embodiments,including multi-top or predictive entry modes. Other examples of userinput interface devices include a scroll wheel 37 and a back button 36.Of course, it will be appreciated that other user input interfacedevices (e.g., a stylus or touch screen interface) may be used in otherembodiments.

A cellular antenna 45, for example, a GSM antenna, is preferablypositioned at the lower portion 47 in the housing and can be formed as apattern of conductive traces that make an antenna circuit, whichphysically forms the antenna. This cellular antenna is connected to thecircuitry 48 on the main circuit board 67. In one non-limiting example,the cellular antenna could be formed on an antenna circuit board sectionthat extends from the main circuit board at the lower portion of thehousing. An example of a cellular antenna that could be used or modifiedfor use is disclosed in commonly assigned U.S. Patent Publication No.2006/0172785, the disclosure which is hereby incorporated by referencein its entirety. By placing the cellular antenna 45 adjacent the lowerportion 47 of the housing 21, the distance is advantageously increasedbetween the cellular antenna and the user's head when the phone is inuse to aid in complying with applicable SAR requirements. Also, aseparate keyboard circuit board could be used. The WiFi antenna (notshown in this figure) can be located away from the cellular antenna 45,as explained in greater detail below.

More particularly, a user will typically hold the upper portion of thehousing 21 very close to his head so that the audio output transducer 49is directly next to his ear. Yet, the lower portion 47 of the housing 21where an audio input transducer (i.e., microphone) is located need notbe placed directly next to a user's mouth, and can be held away from theuser's mouth. That is, holding the audio input transducer close to theuser's mouth may not only be uncomfortable for the user, but it may alsodistort the user's voice in some circumstances.

Another important benefit of placing the cellular antenna 45 adjacentthe lower portion 47 of the housing 21 is that this may allow for lessimpact on antenna performance due to blockage by a user's hand. That is,users typically hold cellular phones toward the middle to upper portionof the phone housing, and are therefore more likely to put their handsover such an antenna than they are an antenna mounted adjacent the lowerportion 47 of the housing 21. Accordingly, more reliable performance maybe achieved by placing the cellular antenna 45 adjacent the lowerportion 47 of the housing 21.

Still another benefit of this configuration is that it provides moreroom for one or more auxiliary input/output (I/O) devices 50 to becarried at the upper portion 46 of the housing. Furthermore, byseparating the cellular antenna 45 from the auxiliary I/O device(s) 50,this may allow for reduced interference therebetween.

Examples of auxiliary I/O devices 50 include a WiFi or WLAN (e.g.,Bluetooth, IEEE 802.11) antenna for providing WLAN communicationcapabilities, as will be explained in greater detail below, and/or asatellite positioning system (e.g., GPS, Galileo, etc.) antenna forproviding position location capabilities, as will be appreciated bythose skilled in the art. Other examples of auxiliary I/O devices 50include a second audio output transducer (e.g., a speaker for speakerphone operation), and a camera lens for providing digital cameracapabilities, an electrical device connector (e.g., USB, headphone,secure digital (SD) or memory card, etc.).

It should be noted that the term “input/output” as used herein for theauxiliary I/O device(s) 50 means that such devices may have input and/oroutput capabilities, and they need not provide both in all embodiments.That is, devices such as camera lenses may only receive an opticalinput, for example, while a headphone jack may only provide an audiooutput.

The device 20 further illustratively includes a display 22, for example,a liquid crystal display (LCD) carried by the housing 21 and connectedto the circuitry 48. A back button 36 and scroll wheel 37 can also beconnected to the circuitry 48 for allowing a user to navigate menus,text, etc., as will be appreciated by those skilled in the art. Thescroll wheel 37 may also be referred to as a “thumb wheel” or a “trackwheel” in some instances. The keypad 23 illustratively includes aplurality of multi-symbol keys 24 each having indicia of a plurality ofrespective symbols thereon. The keypad 23 also illustratively includesan alternate function key 25, a next key 26, a space key 27, a shift key28, a return (or enter) key 29, and a backspace/delete key 30.

The next key 26 is also used to enter a “*” symbol upon first pressingor actuating the alternate function key 25. Similarly, the space key 27,shift key 28 and backspace key 30 are used to enter a “0” and “#”,respectively, upon first actuating the alternate function key 25. Thekeypad 23 further illustratively includes a send key 31, an end key 32,and a convenience (i.e., menu) key 39 for use in placing cellulartelephone calls, as will be appreciated by those skilled in the art.

Moreover, the symbols on each key 24 are arranged in top and bottomrows. The symbols in the bottom rows are entered when a user presses akey 24 without first pressing the alternate function key 25, while thetop row symbols are entered by first pressing the alternate functionkey. As seen in FIG. 2, the multi-symbol keys 24 are arranged in thefirst three rows on the keypad 23 below the send and end keys 31, 32.Furthermore, the letter symbols on each of the keys 24 are arranged todefine a QWERTY layout. That is, the letters on the keypad 23 arepresented in a three-row format, with the letters of each row being inthe same order and relative position as in a standard QWERTY keypad.

Each row of keys (including the fourth row of function keys 25-29) isarranged in five columns. The multi-symbol keys 24 in the second, third,and fourth columns of the first, second, and third rows have numericindicia thereon (i.e., 1 through 9) accessible by first actuating thealternate function key 25. Coupled with the next, space, and shift keys26, 27, 28, which respectively enter a “*”, “0”, and “#” upon firstactuating the alternate function key 25, as noted above, this set ofkeys defines a standard telephone keypad layout, as would be found on atraditional touch-tone telephone, as will be appreciated by thoseskilled in the art.

Accordingly, the mobile wireless communications device 20 as describedmay advantageously be used not only as a traditional cellular phone, butit may also be conveniently used for sending and/or receiving data overa cellular or other network, such as Internet and email data, forexample. Of course, other keypad configurations may also be used inother embodiments. Multi-tap or predictive entry modes may be used fortyping e-mails, etc. as will be appreciated by those skilled in the art.

The cellular antenna 45 is preferably formed as a multi-frequency bandantenna, which provides enhanced transmission and receptioncharacteristics over multiple operating frequencies. More particularly,the cellular antenna 45 is designed to provide high gain, desiredimpedance matching, and meet applicable SAR requirements over arelatively wide bandwidth and multiple cellular frequency bands. By wayof example, the cellular antenna 45 preferably operates over five bands,namely a 850 MHz Global System for Mobile Communications (GSM) band (GSM850), a 900 MHz GSM band, a DCS band, a PCS band, and a WCDMA band(i.e., up to about 2100 MHz) (or CDMA 850/1900), although it may be usedfor other bands/frequencies as well. To conserve space, the cellularantenna 45 may advantageously be implemented in three dimensionsalthough it may be implemented in two-dimensional or planar embodimentsas well.

The mobile wireless communications device shown in FIGS. 1 and 2 canincorporate e-mail and messaging accounts and provide differentfunctions such as composing e-mail, PIN messages, and SMS messages. Thedevice can manage messages through an appropriate menu that can beretrieved by choosing a messages icon. An address book function couldadd contacts, allow management of an address book, set address bookoptions and manage SIM card phone books. A phone menu could allow forthe making and answering of phone calls using different phone features,managing phone call logs, setting phone options, and viewing phoneinformation. A browser application could permit the browsing of webpages, configuring a browser, adding bookmarks, and changing browseroptions. Other applications could include a task, memo pad, calculator,alarm and games, as well as handheld options with various references.

A calendar icon can be chosen for entering a calendar program that canbe used for establishing and managing events such as meetings orappointments. The calendar program could be any type of messaging orappointment/meeting program that allows an organizer to establish anevent, for example, an appointment or meeting.

A non-limiting example of various functional components that can be usedin the exemplary mobile wireless communications device 20 of FIGS. 1 and2 is further described in the example below with reference to FIG. 3.The device 20 illustratively includes a housing 120, a keypad 140 and anoutput device 160. The output device 160 shown is preferably a display,which is preferably a full graphic LCD. Other types of output devicesmay alternatively be used. A processing device 180 is contained withinthe housing 120 and is coupled between the keypad 140 and the display160. The processing device 180 controls the operation of the display160, as well as the overall operation of the mobile device 20, inresponse to actuation of keys on the keypad 140 by the user.

The housing 120 may be elongated vertically, or may take on other sizesand shapes (including clamshell housing structures). The keypad mayinclude a mode selection key, or other hardware or software forswitching between text entry and telephony entry.

In addition to the processing device 180, other parts of the mobiledevice 20 are shown schematically in FIG. 3. These include acommunications subsystem 101; a short-range communications subsystem102; the keypad 140 and the display 160, along with other input/outputdevices 106, 108, 110 and 112; as well as memory devices 116, 118 andvarious other device subsystems 121. The mobile device 20 is preferablya two-way RF communications device having voice and data communicationscapabilities. In addition, the mobile device 20 preferably has thecapability to communicate with other computer systems via the Internet.

Operating system software executed by the processing device 180 ispreferably stored in a persistent store, such as the flash memory 116,but may be stored in other types of memory devices, such as a read onlymemory (ROM) or similar storage element. In addition, system software,specific device applications, or parts thereof, may be temporarilyloaded into a volatile store, such as the random access memory (RAM)118. Communications signals received by the mobile device may also bestored in the RAM 118.

The processing device 180, in addition to its operating systemfunctions, enables execution of software applications 130A-130N on thedevice 20. A predetermined set of applications that control basic deviceoperations, such as data and voice communications 130A and 130B, may beinstalled on the device 20 during manufacture. In addition, a personalinformation manager (PIM) application may be installed duringmanufacture. The PIM is preferably capable of organizing and managingdata items, such as e-mail, calendar events, voice mails, appointments,and task items. The PIM application is also preferably capable ofsending and receiving data items via a wireless network 141. Preferably,the PIM data items are seamlessly integrated, synchronized and updatedvia the wireless network 141 with the device user's corresponding dataitems stored or associated with a host computer system.

Communication functions, including data and voice communications, areperformed through the communications subsystem 101, and possibly throughthe short-range communications subsystem. The communications subsystem101 includes a receiver 150, a transmitter 152, and one or more antennae154 and 156. In addition, the communications subsystem 101 also includesa processing module, such as a digital signal processor (DSP) 158, andlocal oscillators (LOs) 161. The specific design and implementation ofthe communications subsystem 101 is dependent upon the communicationsnetwork in which the mobile device 20 is intended to operate. Forexample, the mobile device 20 may include a communications subsystem 101designed to operate with the Mobitex™, Data TAC™ or General Packet RadioService (GPRS) mobile data communications networks, and also designed tooperate with any of a variety of voice communications networks, such asAMPS, TDMA, CDMA, PCS, GSM, etc. Other types of data and voice networks,both separate and integrated, may also be utilized with the mobiledevice 20.

Network access requirements vary depending upon the type ofcommunication system. For example, in the Mobitex and DataTAC networks,mobile devices are registered on the network using a unique personalidentification number or PIN associated with each device. In GPRSnetworks, however, network access is associated with a subscriber oruser of a device. A GPRS device therefore requires a subscriber identitymodule, commonly referred to as a SIM card, in order to operate on aGPRS network.

When required network registration or activation procedures have beencompleted, the mobile device 20 may send and receive communicationssignals over the communication network 141. Signals received from thecommunications network 141 by the antenna 154 are routed to the receiver150, which provides for signal amplification, frequency down conversion,filtering, channel selection, etc., and may also provide analog todigital conversion. Analog-to-digital conversion of the received signalallows the DSP 158 to perform more complex communications functions,such as demodulation and decoding. In a similar manner, signals to betransmitted to the network 141 are processed (e.g., modulated andencoded) by the DSP 158 and are then provided to the transmitter 152 fordigital to analog conversion, frequency up conversion, filtering,amplification and transmission to the communication network 141 (ornetworks) via the antenna 156.

In addition to processing communications signals, the DSP 158 providesfor control of the receiver 150 and the transmitter 152. For example,gains applied to communications signals in the receiver 150 andtransmitter 152 may be adaptively controlled through automatic gaincontrol algorithms implemented in the DSP 158.

In a data communications mode, a received signal, such as a text messageor web page download, is processed by the communications subsystem 101and is input to the processing device 180. The received signal is thenfurther processed by the processing device 180 for an output to thedisplay 160, or alternatively to some other auxiliary I/O device 106. Adevice user may also compose data items, such as e-mail messages, usingthe keypad 140 and/or some other auxiliary I/O device 106, such as atouchpad, a rocker switch, a thumb-wheel, or some other type of inputdevice. The composed data items may then be transmitted over thecommunications network 141 via the communications subsystem 101.

In a voice communications mode, overall operation of the device issubstantially similar to the data communications mode, except thatreceived signals are output to a speaker 110, and signals fortransmission are generated by a microphone 112. Alternative voice oraudio I/O subsystems, such as a voice message recording subsystem, mayalso be implemented on the device 20. In addition, the display 160 mayalso be utilized in voice communications mode, for example to displaythe identity of a calling party, the duration of a voice call, or othervoice call related information.

Any short-range communications subsystem enables communication betweenthe mobile device 20 and other proximate systems or devices, which neednot necessarily be similar devices. For example, the short-rangecommunications subsystem may include an infrared device and associatedcircuits and components, or a Bluetooth™ communications module toprovide for communication with similarly-enabled systems and devices.

It should be understood that GSM is one type of preferred communicationssystem and uses a radio interface that can have an uplink frequency bandand downlink frequency band with about 25 MHz bandwidth, typicallysubdivided into 124 carrier frequency channels, each spaced about 200KHz apart as non-limiting examples. Time division multiplexing can beused to allow about 8 speech channels per radio frequency channel,giving 8 radio time slots and 8 burst periods grouped into what iscalled a TDMA frame. For example, a channel data rate could be about270.833 Kbps and a frame duration of about 4.615 milliseconds (MS) inone non-limiting example. The power output can vary from about 1 toabout 2 watts.

Linear predictive coding (LPC) can also be used to reduce the bit rateand provide parameters for a filter to mimic a vocal track with speechencoded at about 13 Kbps. Four different cell sizes can be used in a GSMnetwork, including macro, micro, pico and umbrella cells. A base stationantenna can be installed on a master building above the average rooftoplevel in a macrocell. In a microcell, the antenna height can be underthe average rooftop level and used in urban areas. Microcells typicallyhave a diameter of about a few dozen meters and are used indoors.Umbrella cells can cover shadowed regions or smaller cells. Typically,the longest distance for the GSM specification covered by an antenna isabout 22 miles depending on antenna height, gain and propagationconditions.

GSM systems typically include a base station subsystem, a network andswitching subsystem, and a General Packet Radio Service (GPRS) corenetwork. A subscriber identify module (SIM) is usually implemented inthe communications device, for example, the well known SIM card, similarto a smart card containing the subscription information and phone bookof a user. The user can also switch handsets or could change operatorsby changing a SIM.

The GSM signaling protocol has three general layers. Layer 1 is aphysical layer using channel structures above the air interface. Layer 2is the data link layer. Layer 3 is a signaling protocol, which includesthree sublayers. These include a Radio Resources Management sublayer tocontrol the setup, maintenance and termination of radio and fixedchannels, including handovers. A Mobility Management sublayer managesthe location updating and registration procedures and secures theauthentication. A Connection Management sublayer handles general callcontrol and manages supplementary services and the short messageservice. Signaling between different entities such as the Home LocationRegister (HLR) and Visiting Location Register (VLR) can be accomplishedthrough a Mobile Application Part (MAP) built upon the TransactionCapabilities Application Part (TCAP) of the top layer of the SignalingSystem No. 7.

A Radio Resources Management (RRM) sublayer can oversee the radio andfixed link establishment between the mobile station and an MSE.

It is also possible to used Enhanced Data Rates for GSM Evolution(EDGE), as an enhancement to General Packet Radio Service (GPRS)networks. EDGE can use 8 Phase Shift Keying (8 PSK) and Gaussian MinimumShift Keying (GMSK) for different modulation and coding schemes. Athree-bit word can be produced for every changing carrier phase. A rateadaptation algorithm can adapt the Modulation and Coding Scheme (MCS)according to the quality of the radio channel and the bit rate androbustness of data transmission. Base stations are typically modifiedfor EDGE use.

FIG. 4 is a top plan view showing the interior of a mobile wirelesscommunications device 200, such as described in FIGS. 1-3, but thatincorporates the first and second antenna designs described above.Reference numerals begin in the 200 series for the description relativeto FIGS. 4-6. The device 200 shown in FIG. 4 includes a printed circuitboard 202 and various transducers 204 having a function as describedbefore. The main cellular antenna 206 is illustrated at the bottomportion of the housing 208 and corresponds to the antenna describedbefore, and operative as a multi-frequency antenna as described before.The WiFi antenna 210 is positioned at the upper right corner inside thehousing in this non-limiting example and shown as a rectangularconfigured antenna. It is operative at the 2.4 GHz frequency band inaccordance with a non-limiting example for WiFi, WLAN and similarapplications. It could be used for other applications in somenon-limiting examples. A battery 212 and other electronic components 214are shown positioned on the circuit board 202 as illustrated. Thisantenna 210 has its feeding point 210 a at the bottom edge or formed“leg” 210 b and toward the cellular antenna 206 as illustrated.

FIG. 5 is a fragmentary, side-elevation view showing the printed circuitboard 202 that is operative as a ground plane. The WiFi antenna 210 ispreferably formed as an inverted-F antenna and is bottom fed. This WiFiantenna 210 is positioned away from the cellular antenna 206 formed as aGSM antenna (or CDMA) in this non-limiting example. The cellular antenna206 is positioned at the lower portion of the device housing, and can beconfigured as described before. The WiFi antenna 210 is positionedtoward the upper portion of the housing and is bottom fed, such that thelower horizontal leg 210 b that forms part of the inverted-F ispositioned towards the cellular antenna 206.

FIG. 6 is a plan view showing the feeding point 210 a and a groundingpoint 210 c positioned at lower corners on the “leg” 210 b relative tothe cellular antenna 206, as illustrated. The opening gap 210 d formedby the inverted-F or monopole design is positioned opposite from thecellular antenna 206, towards the top or upper portion of the device asillustrated.

It should be understood that the design of the inverted-F or monopoleantenna 210 can vary depending on end-use requirements and the nature ofthe housing, circuit board, proximity to the main cellular antenna, andother factors that could be determined by those skilled in the art.Typically, the height of the inverted-F is established by the leg 210 brelative to the ground plane defined by the PCB 202. Input impedance atthe feeding point 210 a can vary from about 30 to about 75 ohms, butcentered at 50 ohms, in some non-limiting examples. Resonances can varydepending on the type of feeding lines or traces that are used.

The inverted-F antenna typically is a small size and is designed forease of design and fabrication. This WiFi antenna 210 as described couldbe fed by a microstrip line printed on the printed circuit board 202. Insome cases, the inverted-F antenna could be formed as an ActiveInverted-F Antenna (AIFA) and printed on the PCB 202, for example, witha thickness of about 1 mm in one non-limiting example. Some designscould use a straight-F design and still be printed on a FR-4 or similarsubstrate with other circuit components to provide a low-cost antenna.For example, in a straight-F antenna, an inductive tuning arm could beon the same side of a capacitive arm. In any event, the antenna designsshould be designed such that the opening gap 210 d is positioned to faceaway from the cellular antenna 206, in these non-limiting examples.

In some non-limiting examples, an inverted-F antenna is similar to afree-standing (quarter-wave) monopole positioned above a ground plane,rather than a half-wave printed antenna in some non-limiting examples.The antenna can be formed in an area less than about 10 mm by 10 mm innon-limiting examples. The inductive and capacitive arms of aninverted-F antenna could add to the total antenna length in somedesigns. In other antenna designs, it is possible to have a ground planeedge to determine functional characteristics and the operation band. Anupper part of the “F” could be used for inductive tuning and a lowerpart of the “F” could be used to form a capacitively coupled monopole.

It is possible to apply Method of Moments (MoM) design considerations towire antennas of arbitrary shape to form a Dual Inverted-F Antenna(DIFA). It should be understood that the inverted-F antenna is avariation on a transmission line antenna or bent monopole antenna. Itcould include an offset feed to provide for adjustment of the inputimpedance in some non-limiting examples. Thus, the resulting antennageometry resembles the letter F, rotated to face the ground plane.

Many modifications and other embodiments of the invention will come tothe mind of one skilled in the art having the benefit of the teachingspresented in the foregoing descriptions and the associated drawings.Therefore, it is understood that the invention is not to be limited tothe specific embodiments disclosed, and that modifications andembodiments are intended to be included within the scope of the appendedclaims.

1-25. (canceled)
 26. A mobile wireless communications device,comprising: a housing; radio frequency (RF) circuitry supported withinsaid housing; a first antenna operatively connected to said RF circuitryand configured for cellular phone communications; and a second antennaoperatively connected to said RF circuitry and configured for WiFicommunications, wherein said second antenna comprises an inverted-Fantenna having a substantially rectangular configuration in plan andupper edge forming an opening gap that is pointed away from the firstantenna for isolating first and second antennas from each other, saidsecond antenna including a lower edge and a feeding point and groundingpoint at opposite corners of the lower edge, wherein mutual coupling dueto harmonics between first and second antennas is reduced.
 27. Themobile wireless communications device according to claim 26, and furthercomprising a circuit board supported by said housing, wherein at leastone of said first antenna and second antenna are supported by thecircuit board.
 28. The mobile wireless communications device accordingto claim 27, and further comprising a second circuit board, wherein saidfirst antenna is supported by one of said circuit boards and said secondantenna is supported by the other circuit board.
 29. The mobile wirelesscommunications device according to claim 27, wherein said circuit boardcomprises a ground plane for one of said antennae.
 30. The mobilewireless communications device according to claim 26, wherein at leastone of said first and second antenna are supported by said housing. 31.The mobile wireless communications device according to claim 26, whereinsaid housing includes a lower portion and said first antenna issupported at the lower portion within the housing.
 32. The mobilewireless communications device according to claim 26, wherein saidhousing includes an upper portion and said second antenna is supportedat the upper portion.
 33. The mobile wireless communications deviceaccording to claim 26, wherein said housing comprises a static housing,a flip housing or a sliding housing.
 34. The mobile wirelesscommunications device according to claim 26, wherein said first antennais operative at frequencies in the Global System for Mobile (GSM)communications band.
 35. The mobile wireless communications deviceaccording to claim 26, wherein said second antenna is operative at the2.4 GHz and 5.0 GHz band in accordance with 802.11 standards.
 36. Themobile wireless communications device according to claim 26, whereinsaid second antenna includes a feeding point positioned distal from theopening gap at an opposing end from the opening gap.
 37. The mobilewireless communications device according to claim 26, wherein theopening gap is configured upward towards the upper portion of thehousing.
 38. A method for making a mobile wireless communicationsdevice, which comprises: providing a housing containing radio frequency(RF) circuitry therein; and supporting first and second antennas suchthat first and second antennas are connected to the RE circuitry,wherein the first antenna is configured for cellular phonecommunications and the second antenna is configured for WiFicommunications as a substantially rectangular configured inverted-Fantenna having an upper edge and forming an opening gap that is pointedaway from the first antenna for isolating the first and second antennasfrom each other, wherein said second antenna includes a lower edge and afeeding point and grounding point at opposite corners at the lower edgewherein mutual coupling due to harmonics between first and secondantennas are reduced.
 39. The method according to claim 38, whichfurther comprises supporting a circuit board within the housing andsupporting one of said antenna by said circuit board.
 40. The methodaccording to claim 39r which further comprises forming the circuit boardas a ground plane for first and second antennas.
 41. The methodaccording to claim 39, which further comprises supporting a secondcircuit board within the housing and supporting said first antenna byone of said circuit boards and supporting the second antenna by theother circuit board.
 42. The method according to claim 38, which furthercomprises supporting first and second antenna by the housing.
 43. Themethod according to claim 38, which further comprises supporting thefirst antenna at a lower portion of the housing.
 44. The methodaccording to claim 38, which further comprises supporting the secondantenna at an upper portion of the housing.
 45. The method according toclaim 38, which further comprises forming the housing as a statichousing, a flip housing or a sliding housing.
 46. The method accordingto claim 38, which further comprises forming the first antenna to beoperative at frequencies in the Global System for Mobile (GSM)communications band.
 47. The method according to claim 38, which furthercomprises forming the second antenna to be operative at the 2.4 GHz and5.0 GHz band in accordance with 802.11 standards.